One conventional technique for sample rate conversion uses finite impulse response (FIR) filters or infinite impulse response (IIR) filters to perform the sample rate conversion. However, such circuits are complicated, and involve a large number of circuit elements, such as logic gates. The circuit complexity increases for a high sample rate conversion ratio. The circuit complexity additionally increases to maintain low distortion of a high quality digitized signal. In an integrated circuit implementation, such complicated filters occupy an undesirably large area of the die, and power consumption is undesirably high. Moreover, the quality of the digitized signal is very often difficult to maintain in practice.
An alternative conventional technique employs a cascaded integrator-comb (CIC) filter. However, such a technique is efficient only for integer sample rate conversion ratios. Such a limitation vastly reduces the usefulness of a CIC filter for many sample rate conversion circuit applications that involve non-integer sample rate conversion ratios.